ISSUE apache#691: Move generated files into their own module

Upcoming changes are using GRpc in conjunction with protobuf. GRpc
generates code that created deprecation warnings when compiled with
java 8, so this change moves all generated code out to another module,
so that we don't have to turn off -Werror for all code.

In any case, at some point we should split the bookkeeper client out
from the server module, at which point we would need the definitions
on a common place.

Author: Ivan Kelly <ivank@apache.org>

Reviewers: Enrico Olivelli <eolivelli@gmail.com>, Jia Zhai <None>, Sijie Guo <sijie@apache.org>

This closes apache#711 from ivankelly/proto-module, closes apache#691

bookkeeper-proto/pom.xml

@@ -0,0 +1,69 @@
+<?xml version="1.0"?>
+<!--
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+-->
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <parent>
+    <artifactId>bookkeeper</artifactId>
+    <groupId>org.apache.bookkeeper</groupId>
+    <version>4.6.0-SNAPSHOT</version>
+  </parent>
+  <artifactId>bookkeeper-proto</artifactId>
+  <name>Apache BookKeeper :: Protocols</name>
+  <properties>
+    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+  </properties>
+  <dependencies>
+    <dependency>
+      <groupId>com.google.protobuf</groupId>
+      <artifactId>protobuf-java</artifactId>
+      <version>${protobuf.version}</version>
+      <scope>compile</scope>
+    </dependency>
+  </dependencies>
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.rat</groupId>
+        <artifactId>apache-rat-plugin</artifactId>
+        <configuration>
+          <excludes>
+            <!-- exclude generated file //-->
+            <exclude>**/DataFormats.java</exclude>
+            <exclude>**/BookkeeperProtocol.java</exclude>
+          </excludes>
+        </configuration>
+      </plugin>
+      <plugin>
+        <groupId>org.xolstice.maven.plugins</groupId>
+        <artifactId>protobuf-maven-plugin</artifactId>
+        <version>0.5.0</version>
+        <configuration>
+          <protocArtifact>com.google.protobuf:protoc:3.4.0:exe:${os.detected.classifier}</protocArtifact>
+          <checkStaleness>true</checkStaleness>
+        </configuration>
+        <executions>
+          <execution>
+            <goals>
+              <goal>compile</goal>
+            </goals>
+          </execution>
+        </executions>
+      </plugin>
+    </plugins>
+  </build>
+</project>

bookkeeper-server/pom.xml

@@ -35,10 +35,9 @@
       <version>${project.parent.version}</version>
     </dependency>
     <dependency>
-      <groupId>com.google.protobuf</groupId>
-      <artifactId>protobuf-java</artifactId>
-      <version>${protobuf.version}</version>
-      <scope>compile</scope>
+      <groupId>org.apache.bookkeeper</groupId>
+      <artifactId>bookkeeper-proto</artifactId>
+      <version>${project.parent.version}</version>
     </dependency>
     <dependency>
       <groupId>org.slf4j</groupId>
@@ -294,8 +293,6 @@
         <configuration>
           <excludes>
             <!-- exclude generated file //-->
-            <exclude>**/DataFormats.java</exclude>
-            <exclude>**/BookkeeperProtocol.java</exclude>
             <exclude>**/target/**/*</exclude>
             <exclude>**/.classpath</exclude>
             <exclude>**/.gitignore</exclude>
@@ -372,22 +369,6 @@
           </execution>
         </executions>
       </plugin>
-      <plugin>
-        <groupId>org.xolstice.maven.plugins</groupId>
-        <artifactId>protobuf-maven-plugin</artifactId>
-        <version>0.5.0</version>
-        <configuration>
-          <protocArtifact>com.google.protobuf:protoc:3.4.0:exe:${os.detected.classifier}</protocArtifact>
-          <checkStaleness>true</checkStaleness>
-        </configuration>
-        <executions>
-          <execution>
-            <goals>
-              <goal>compile</goal>
-            </goals>
-          </execution>
-        </executions>
-      </plugin>
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-checkstyle-plugin</artifactId>

pom.xml

@@ -52,6 +52,7 @@
   </ciManagement>
   <modules>
     <module>buildtools</module>
+    <module>bookkeeper-proto</module>
     <module>bookkeeper-common</module>
     <module>bookkeeper-stats</module>
     <module>bookkeeper-server</module>